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Stock Option and Incentive Plan Stock and Units (Narrative) (Details)
$ / shares in Units, $ in Thousands
12 Months Ended
Feb. 04, 2022
USD ($)
shares
Feb. 01, 2022
USD ($)
Feb. 05, 2021
USD ($)
shares
Feb. 06, 2020
USD ($)
shares
Dec. 31, 2022
USD ($)
days
$ / shares
shares
Dec. 31, 2021
USD ($)
$ / shares
shares
Dec. 31, 2020
USD ($)
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Shares issued | shares         156,836,767 156,623,749  
Vesting Period         4 years    
Stock based compensation expense         $ 50,700 $ 49,700 $ 43,000
Common Stock, Value, Issued         $ 1,568 $ 1,565  
Restricted Stock [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Shares issued | shares         41,818 57,383 29,630
LTIP Units [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Value Of LTIP Units Issued         $ 28,900 $ 23,800 $ 26,300
Weighted average price (per unit) | $ / shares         $ 103.06 $ 84.43 $ 127.14
Expected life assumed to calculate per unit fair value per LTIP unit (in years)         5 years 8 months 12 days 5 years 8 months 12 days 5 years 8 months 12 days
Risk-free rate         1.71% 0.65% 1.47%
Expected price volatility         31.00% 30.00% 18.00%
MYLTIP 2019 [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Final awards percentage of target 69.00%            
Value of MYLTIP Awards $ 8,600            
Forfeitures, in units | shares 144,043            
MYLTIP 2018              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Final awards percentage of target     29.20%        
Value of MYLTIP Awards     $ 4,600        
Forfeitures, in units | shares     285,925        
MYLTIP 2017 [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Final awards percentage of target       83.80%      
Value of MYLTIP Awards       $ 17,600      
Forfeitures, in units | shares       270,942      
Employee Stock              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of shares issued | shares         9,813 9,846 7,195
Weighted Average Price of Shares Purchased | $ / shares         $ 87.30 $ 89.73 $ 90.53
Number of Business Days, Average Closing Price | days         10    
MYLTIP 2022              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Value of MYLTIP Awards   $ 17,300          
Vesting Period   3 years          
Boston Properties Limited Partnership | LTIP Units [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of shares issued | shares         280,616 281,640 207,181
Boston Properties Limited Partnership | MYLTIP 2022              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of shares issued | shares         254,061    
Boston Properties Limited Partnership | MYLTIP 2021              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of shares issued | shares           352,021  
Restricted Stock [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Employee and director payment per share (in dollars per share) | $ / shares         $ 0.01    
Common Stock, Value, Issued         $ 4,700 $ 5,800 $ 4,000
Common Stock Weighted Average Price (in dollars per share) | $ / shares         $ 111.47 $ 100.60 $ 133.81
LTIP and MYLTIP Units [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Employee and director payment per share (in dollars per share) | $ / shares         $ 0.25    
Ltips (including vested MYLTIPS) And Restricted Stock [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Unrecognized compensation expenses         $ 20,600    
Unvested MYLTIP Units [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Unrecognized compensation expenses         $ 4,900    
Weighted-average period (years)         1 year 10 months 24 days